<template>
  <div>
    <table
      border="1"
      width="700"
      style="border-collapse: collapse"
    >
      <caption>
        购物车
      </caption>
      <thead>
        <tr>
          <th>
            <input type="checkbox" v-model="isAll" /> <span>全选</span>
          </th>
          <th>名称</th>
          <th>价格</th>
          <th>数量</th>
          <th>总价</th>
          <th>操作</th>
        </tr>
      </thead>
      <tbody>
        <tr v-for="(item, index) in goodList" :key="index">
          <th><input type="checkbox" v-model="item.checked" /></th>
          <th>{{ item.name }}</th>
          <th>{{ item.price }}</th>
          <th>
            <button :disabled="item.num <= 0" @click="item.num--">-</button>
              {{ item.num }}
            <button @click="item.num++">+</button>  
          </th>
          <th>{{ item.price * item.num }}</th>
          <th><button @click="delFn(index)">删除</button></th>
        </tr>
      </tbody>
      <tfoot>
        <tr>
          <td>合计:</td>
          <td colspan="5">
            {{ allsPrice }}
          </td>
        </tr>
      </tfoot>
    </table>
  </div>
</template>

<script>
export default {
  data() {
    return {
      goodList: [
        {
          name: "诸葛亮",
          price: 1000,
          num: 1,
          checked: false,
        },
        {
          name: "蔡文姬",
          price: 1500,
          num: 1,
          checked: true,
        },
        {
          name: "妲己",
          price: 2000,
          num: 1,
          checked: false,
        },
        {
          name: "鲁班",
          price: 2200,
          num: 1,
          checked: false,
        },
      ],
      // allsPrice: 0, 
    };
  },
  methods: {
    delFn(index) {
      this.goodList.splice(index, 1)
    }
  },
  computed: {
    isAll: {
      set(val) {
        return this.goodList.forEach((item) => item.checked = val)
      },
      get() {
        return this.goodList.every((item) => item.checked)
      }
    },
    allsPrice() {
      return this.goodList.reduce((sum, item) => {
        if (item.checked) {
          sum += item.num * item.price
        }
        return sum
      }, 0)
    }
  }
};
</script>

<style>
</style>